Valve tappet



Feb 14, 1967 A. B. MELLENG 3,303,833

VALVE TAPPET Filed Sept. 21, 1964 2 Sheets-Sheet l INVENTOR.

Feb. 14, 196? a. MELUNG 3,303,833

VALVE TAPPET Filed Sept. 21, 1.964 2 Sheets-Sheet 2 jlzaj ---r I I 37 i5 INVENTOR.

Aubrey .5 Mew/1 ATTOIZN EY United States Patent Ofiice 33%,833 Patented Feb. 14 1967 3,303,833 VALVE TAPPET Aubrey B. Meliing, 754 Bloomfield Blvd, Jackson, Mich. 49203 Filed Sept. 21, 1964. Ser. No. 398,019 11 Claims. (Cl. ill-90) This invention relates to valve operating means quite commonly designated valve tappets.

The main objects of this invention are:

First, to provide a valve tappet in which the end is tiltably supported as the cam with which it is operatively associated is rotated.

Second, to provide a tappet assembly which includes a tiltable cam engaging member which is efiiciently lubricated.

Third, to provide a tappet structure having these advantages in which the cam engaging member is supported and retainingly connected to the body portion of the tappet to permit handling thereof as a unit and to maintain the cam engaging member in assembled relation to the tappet body.

Fourth, to provide a tappet structure having these characteristics which may be economically produced and is durable in use.

Other Objects relating structural and use details and economies of the invention will appear from the description to follow. The invention is defined and pointed out in the claims. A preferred embodiment of the invention is illustrated in the accompanying drawing, in which:

FIG. 1 is a fragmentary view mainly in vertical section of a valve assembly embodying my invention, the tappet unit and some of the associated parts being shown in full lines.

FIG. 2 is an enlarged longitudinal sectional view of the tappet unit removed from the body on a line corresponding to line 2-2 of FIG. 3.

FIG. 3 is a sectional view of the tappet unit on a line corresponding to line 3-3 of FIG. 2.

FIG. 4 is a cross sectional view on a line corresponding to line 4-4 of FIG. 2.

FIG. 5 is a fragmentary view mainly in section showing the adaptation of my invention to another form of engine structure.

FIG. 6 is a fragmentary view of another embodiment of my invention, some of the parts being shown conventionally.

FIG. 7 is an enlarged fragmentary view illustrating in structural detail a modified form or embodiment of my invention.

FIG. 8 is an enlarged fragmentary view of the embodiment of my invention shown in FIG. 7 illustrating the operative relation of the embodiment shown in FIG. 7 to a cam.

FIG. 9 is a fragmentary view partially in section of the embodiment of my invention shown in FIGS. 6, 7 and 8 mainly in section on a line corresponding to line 9-9 of FIG. 6.

FIG. 10 is a fragmentary view illustrating a slightly modified form or embodiment of my invention.

It should be understood that in the accompanying drawings I have not attempted to illustrate the parts in the proportions they would have in a commercial embodiment and that certain of the parts are shown mainly conven tionally.

The engine body member designated generally by the numeral 1 is commonly provided with a plurality of cylinders designated by the numeral 2 with pistons 3.

The inlet connection 4 is provided with a valve 5 coacting with the valve seat 6. The valve 5 is provided with a stem 7 disposed in and reciprocatingly mounted in the bearings 8. The stem is provided with a thrust collar 9 with which the spring 10 supportedly mounted on the bearing member coacts. These parts are mainly shown conventionally as they do vary in different makes or types of engines.

It will be understood that the cam shaft 11 illustrated in FIG. 1 is provided with a plurality of cams 12 which coact with the tappet units embodying my invention. In FIG. 6 I illustrate three units and it will be understood that they vary according to the number of cylinders in the engine. The engine body member 13 is provided with bearings 14- for the tappet members 15. These body members 13 are provided with oil conduits 16 which open to the tappet bearings 14. The tappet body members 15 have reduced intermediate portions 17 and bearing portions 18 which are in slidable engagement with the tappet bearings 14. It will be understood that the bearing portions 18 have a close sliding fit with the bearings. At its inner end the tappet member 15 is provided with a seat 19 for the bearing 29 which coacts with the spherically curved bearing 21 on the valve stem. The bearing 2% is provided with a lubricant opening 22 for lubricating the bearing on the end of the valve stem. This member 29 is a substantial sealing fit in the inner end of the tappet body member.

At its outer end the tappet body member is provided with a spherically curved outwardly facing bearing 23 for the cam engaging member 24, the inner side of which is convexly curved. The outer side 25 is desirably planar or fiat, as illustrated in the drawing. At its inner end the concave cam engaging member seat 23 has a central bore 26 opening to the chamber in the tappet and the cam engaging member has a stem 27 projecting through its opening 26, the opening being such size as to permit some tilting movement of the cam engaging member; such movement being indicated by dotted lines in FIG. 3. It will be understood that the movement varies considerably in use depending on the structural features which are present or involved.

In this embodiment the cam engaging member stem projects into the tappet body member and is provided with an annular groove 28 with which the retaining clip 29 is in clutching engagement. This clip 29 is desirably of springably resilient material and while it not only serves to retain the cam engaging member in assembled relation to the body portion of the tappet, it also springably urges the cam engaging member on its seat and prevents undesired disoharge of lubricant. However it is desirable that the cam engaging member be effectively lubricated and also that some lubricant be discharged upon the cam. To insure that result in the embodiment of the invention illustrated the cam engaging member is provided with an opposed pair of lubricant conduit grooves 34 shown in full lines in FIG. 2 and by the dotted lines in FIG. 3.

In the embodiment of my invention illustrated in FIGS. 1 to 4 inclusive a lubricant passage 31 connects the lubricant chamber of the tappet body member to the cam engaging bearing.

I have not attempted to illustrate the varying degrees of tiltable movement of the cam engaging member in FIG, 1, 2, 3 and 5, but it will be understood that that varies and in some cases it is only of the order of a fraction. However, the cam engaging member does maintain an effective bearing engagement with cams which may vary substantially in shape rather than a point contact and compensates for small misalignments between the cam shaft and the tappet. Manufacturers attempt to produce cams and align the tappet bearings accurately but when it comes to production they do vary somewhat and their relation may vary in the degree of wear.

FIGS. 6 to 10 inclusive illustrate a modified form of the invention in which the cam engaging member 32 does not have the stem of the embodiment shown in FIGS. 1 to inclusive. In FIG. 6 I illustrate a frame member 33 which is adapted to support a plurality of tappet body members 34 which are substantially the same as in the embodiment shown in FIGS. 1 to 5 inclusive except, as stated, the cam engaging member 32 does not have a stem portion but has a spherically curved inner surface 35. The concave seats 36 have conduits 37 connected at their inner ends to the lubricant chamber of the tappet body members by the passages or lubricant outlets 38. The tappet members 32 have planar faces 39 which engage the cams designated 40 which functionally conform to the cams 12 of the embodiment illustrated in FIGS. 1 and 2.

In the embodiment shown in FIG. 8 I illustrate by dotted lines 41 the commonly used form of cam and by full lines the form of cam which I prefer to use and which may be used with tappet units embodying my invention. In the embodiment of my invention illustrated in FIGS. 6, 7, 8 and 9 the cam engaging members 32 are retained in the sockets provided therefor by means of the collars 42 which are pressed on or otherwise secured to the tappet body members, the securing means not being illustrated.

In the embodiment of my invention shown in FIG. the cam engaging members 32 are retained by rolling or pressing in outer portions 43 which must be done after the cam engaging members has been inserted, otherwise the structure is the same as illustrated in FIGS. 6, 7, 8 and 9.

In FIGS. 3, 6, 8 and 9 I have illustrated the cam engaging member in different tilted positions. It should be understood that that varies greatly in commercial practice not only from structure but from wear. In some embodiments the tilting movement is relatively slight as indicated by dotted lines in FIG. 3. The maintaining of effective contact with the cam is an important feature of the invention. However, it should be understood that in the event of unexpected or undue wear on the cam or cam engaging member they may be readily replaced at very little cost.

All forms of the tappet prevent the cam engaging planar face of the cam engaging member from riding on the edge of the cam which is commonly tapered axially as appears in FIG. 6. The cam engaging members 24 and 32 tilt sufficiently in a vertical plane through the axis of the cam shaft to establish a line contact axially along the tapered periphery of the cam. This not only eliminates high point contact loads that would quickly wear or break off the high edges of the cams, but also permits the use of stiffer valve springs 10 for more rapid and secure closing of the valves.

The wide angle of tilt of the cam contacting members 32 in planes perpendicular to the axis of the cam shaft permits the use of the wider or longer radius cam lobe flanks shown at 40. This in turn moves the line contact between the cam and the cam contacting member closer toward the center of the tappet. This provides longer line contact across a longer chord of the tappet, reducing unit bearing pressure. This in turn permits use of stronger valve springs and/ or smaller diameter and lighter tappets.

With both forms of the tappets, the cam contact eccentric to the axis of the tappet tends to rotate both the semi-spherical cam contacting member in the tappet body 15 and the tappet body in .its bearing bore 14. This distributes the wear and provides a longer lasting tappet and cam.

I have illustrated and described my invention in a highly practical embodiment thereof. I have not attempted to illustrate or describe other modifications or adaptations as it is believed that this disclosure will enable those skilled in the art to embody or adapt my invention as may be desired.

Having thus described the invention, what is claimed as new and desired to secure by Letters Patent is:

1. A structure of the class described comprising a body member, a valve actuating cam, a spring seated valve having a stern reciprocatingly mounted on said body member, the stem having a spherically curved thrust member on its outer end, said body member having an elongated tappet body member holder aligned with said stern, a tubular tappet body member reciprocatingly mounted in said holder and having a socket in its inner end coacting with said thrust member on said valve stem, said socket having a lubricant discharge opening disposed centrally thereof, said tappet body member also having a conically curved outwardly facing cam engaging member seat in its outer end and a central bore opening to said seat, a cam engaging member having a planar face coacting with said cam disposed in said seat in said tappet body member seat and having an inwardly facing centrally disposed stem disposed through said bore in the outer end of said tappet 'body member and dimensioned relative thereto to permit tilting movement of said cam engaging member while it is in thrust engagement with said cam, said tappet body member having a lubricant conduit therein opening to said cam engaging member seat and radially disposed lubricant conduit grooves in its inner side, said stem on said cam engaging thrust bearing member having an annular groove therein, and a springably resilient clip engaged in said groove and acting to retain and urge said thrust bearing member in engagement with its said seat while permitting limited lateral tilting movement thereof.

2. A structure of the class described comprising a body member, a valve actuating cam, a spring seated valve having a stem reciprocatingly mounted on said body member, said body member having an elongated tappet body member holder aligned with said stem, a tubular tappet body member reciprocatingly mounted in said holder and operatively associated with said valve stem and having a lubricant discharge opening disposed centrally thereof, said tappet body member having a conically curved outwardly facing cam engaging member seat in its outer end and a central bore opening to said seat, a cam engaging member having a planar face coacting with said cam disposed in said seat in said tappet body member seat and having an inwardly facing centrally disposed stem disposed through said bore in the outer end of said tappet body member and dimensioned relative thereto to permit tilting movement of said cam engaging member while it is in thrust engagement with said cam, said tappet body member having a lubricant conduit therein opening to said cam engaging member seat and radially disposed lubricant conduit grooves in its inner side, said stem on said cam engagiing thrust bearing member having an annular groove therein, and a springably resilient clip engaged in said groove and acting to retain and urge said thrust bearing member in engagement with its said seat while permitting limited lateral tilting movement thereof.

3. A structure of the class described comprising a body member, a valve actuating cam, a spring seated valve having a stem reciprocatingly mounted on said body member, the stem having a spherically curved thrust member on its outer end, said body member having an elongated tappet body member holder aligned with said stem, a tubular tappet body member reciprocatingly mounted in said holder and having a socket in its inner end coacting with said thrust member on said valve stem, said socket having a lubricant discharge opening disposed centrally thereof, said tappet body member also having a conically curved outwardly facing cam engaging member seat in its outer end and a central bore opening to said seat, a cam engaging member having a planar face coacting with said cam disposed in said seat in said tappet body member seat and having an inwardly facing centrally disposed stem disposed through said bore in the outer end of said tappet body member and dimensioned relative thereto to permit tilting movement of said cam engaging member while it is in thrust engagement with said cam, said tappet body member having a lubricant conduit therein opening to said cam engaging member seat and radially disposed lubricant conduit grooves in its inner side.

4. A structure of the class described comprising a body member, a valve actuating cam, a spring seated valve having a stem reciprocatingly mounted on said body memher, said body member having an elongated tappet body member holder aligned with said stem, a tubular tappet body member reciprocatingly mounted in said holder and operatively associated with said valve stem and having a lubricant discharge opening, said tappet body member having a conically curved outwardly facing cam engaging member seat in its outer end and a central bore opening to said seat, and a cam engaging member having a planar face coacting with said cam disposed in said seat in said tappet body member seat and having an inwardly facing centrally disposed stem disposed through said bore in the outer end of said tappet body member and dimensioned relative thereto to permit tilting movement of said cam engaging member while it is in thrust engagement with said cam, said tappet body member having a lubricant conduit therein opening to said cam engaging member seat and radially disposed lubricant conduit grooves in its inner side.

5. A structure of the class described comprising a body member, a valve actuating cam, a spring seated valve having a stem reciprocatingly mounted on said body member, the stem having a spherically curved thrust member on its outer end, said body member having an elongated tappet body member holder aligned with said stem, a tubular tappet body member reciprocatingly mounted in said holder and having a socket in its inner end coacting with said thrust member on said valve stem, said socket having a lubricant discharge opening disposed centrally thereof, said tappet body member also having a conically curved outwardly facing cam engaging member seat in its outer end and a central bore opening to said seat, and a cam engaging member having a planar face coacting with said cam disposed in said seat in said tappet body member seat and having an inwardly facing centrally disposed stem disposed through said bore in the outer end of said tappet body member and dimensioned relative thereto to permit tilting movement of said cam engaging member while it is in thrust engagement with said cam.

6. A structure of the class described comprising a body member, a valve actuating cam, a spring seated valve having a stem reciprocatingly mounted on said body member, said body member having an elongated tappet body member holder aligned with said stern, a tubular tappet body member reciprocatingly mounted in said holder and operatively associated with said valve stem and having a lubricant discharge opening, said tappet body member having a conically curved outwardly facing cam engaging member seat in its outer end and a central bore opening to said seat, and a cam engaging member having a planar face coacting with said cam disposed in said seat in said tappet body member seat and having an inwardly facing centrally disposed stern disposed through said bore in the outer end of said tappet body member and dimensioned relative thereto to permit tilting movement of said cam engaging member while it is in thrust engagement with said cam,

7. A structure of the class described comprising a body member, a valve having a stem reciprocatingly supported on said body member, a valve actuating cam, said body member having an elongated tappet body member holder aligned with said valve, a cylindrical tubular tappet body member reciprocatingly mounted in said holder and operatively associated with said valve stem, said tappet body member having a concaved outwardly facing cam engaging member seat in its outer end and a central bore opening to said seat, a cam engaging member having a planar face coacting with said cam tiltably supported in said seat in said tappet body member and having an inwardly facing centrally disposed stem disposed through said bore in the outer end of said tappet body member and dimensioned relative thereto to permit tilting movement of said cam engaging member while it is in thrust engagement with said cam, said tappet body member having a lubricant chamber therein and having an intermediate portion with a lubricant supply opening therein, said body member having a lubricant passage therein, said tappet body member having a lubricant conduit therein opening to said cam engaging member seat, said cam engaging member having a lubricant conduit therein, and means engaged with said stem acting to retain said cam engaging member while permitting tilting movement thereof.

8. A structure of the class described comprising a body member, a valve, a valve actuating cam, said body member having an elongated tappet body member holder aligned with said valve, a tappet body member reciprocatingly mounted in said holder and operatively associated with said valve, said tappet body member having a concaved outwardly facing cam engaging member seat in its outer end and a central bore opening to said seat, a cam engaging member having a planar face coacting with said cam and tiltably supported in said seat in said tappet body member and having an inwardly facing centrally disposed stern disposed through said bore in the outer end of said tappet body member and dimensioned relative thereto to permit tilting movement of said cam engaging member while it is in thrust engagement with said cam, said tappet body member having a lubricant chamber therein and having an intermediate portion with a lubricant supply open ing therein, said body member having a lubricant passage therein, said cam engaging member having a lubricant conduit therein, and means engaged with said stern acting to retain said cam engaging member while permitting tilting movement thereof.

9. The combination of a body member, a valve and a valve actuating cam having a peripheral bearing portion of substantial width, said body member having a tappet holder operatively associated with said vave, a tappet body member reciprocatingly mounted in said holder and operatively associated with said valve, said tappet body member having a concave outwardly facing cam engaging member seat at its outer end, a cam engaging thrust member having a spherically curved inner portion tiltably supported in said seat and in coacting relation with said cam, there being a lubricant supply connected for said tappet body member, one of said cam engaging member and seat having a lubricant passage therein opposed to the other, said cam engaging member having a planar cam engaging face spaced from the radial center of said spherically curved inner portion by a distance less than the radius of said periphery curved portion, the face portion of said cam throughout the rotating movement thereof having a portion of substantial width disposed in contacting relation to said planar face.

10. The combination of a body member, a valve and a valve actuating cam having a peripheral bearing portion of substantial width, said body member having a tappet holder operatively associated with said valve, a tappet body member reciprocatingly mounted in said holder and operatively associated with said valve, said tappet body member having a spherically curved concave outwardly facing cam engaging member seat at its outer end, and a cam engaging thrust member having a spherically curved face swivelably bearing on and supported in said seat, said cam engaging member having a planer cam engaging face, said planar face comprising a chordal plane of said spherically curved face, the face portion of said cam throughout the rotating movement thereof having a portion of substantial width disposed in contacting relation to said planar face.

11. The device defined in claim 10 in which said cam engaging member is monolithic and said planar surface is spaced beyondthe end of the tappet body member by a distance less than the radius of curvature of said spherical face of said cam engaging member.

References Cited by the Examiner UNITED STATES PATENTS FOREIGN PATENTS Great Britain.

MARK NEWMAN, Primary Examiner.

AL LAWRENCE SMITH, CARLTON R. CROYLE,

Examiners. 

9. THE COMBINATION OF A BODY MEMBER, A VALVE AND A VALVE ACTUATING CAM HAVING A PERIPHERAL BEARING PORTION OF SUBSTANTIAL WIDTH, SAID BODY MEMBER HAVING A TAPPET HOLDER OPERATIVELY ASSOCIATED WITH SAID VAVE, A TAPPET BODY MEMBER RECIPROCATINGLY MOUNTED IN SAID HOLDER AND OPERATIVELY ASSOCIATED WITH SAID VALVE, SAID TAPPET BODY MEMBER HAVING A CONCAVE OUTWARDLY FACING CAM ENGAGING MEMBER SEAT AT ITS OUTER END, A CAM ENGAGING THRUST MEMBER HAVING A SPHERICALLY CURVED INNER PORTION TILTABLY SUPPORTED IN SAID SEAT AND IN COACTING RELATION WITH SAID CAM, THERE BEING A LUBRICANT SUPPLY CONNECTED FOR SAID TAPPET BODY MEMBER, ONE OF SAID CAM ENGAGING MEMBER AND SEAT 